Skip to main content

View Diary: Green diary rescue & open thread (77 comments)

Comment Preferences

  •  19 Million KWh = 328 NJ Homes (0+ / 0-)

    These numbers don't add up:

    The 7.5-megawatt (MW) Jersey-Atlantic Wind Farm

    There's 8,765.81277 hours in a year. * 7.5 megawatts is  65,743,595.775 KWh in a year, but the article says 19 million kilowatt hours in a year:

    The project produces approximately 19 million kilowatt-hours of emission-free electricity per year, which is enough emission-free energy to power over 2,000 homes.

    Maybe the windfarm is generating power for only 1/3 of the windiest hours of the year. But that doesn't add up, either:
    3,210,592 total NJ households in 2008.

    They consumed 635.5 trillion BTUS in 2000 (last data year), which is about 186,246,665,000 kilowatt hours, so average NJ home consumes something like 186,246,665,000 / 3,210,592 = 58,010.0695 kilowatt hours per year.

    19 million kilowatt hours a year total would deliver 58,010.0695 kilowatt hours each to only 327.529344 NJ homes. That's a lot different from 2,000.

    Look, I'm all for windpower, especially in a state like NJ that has structured its economy so much on shipping, storing, refining consuming petrofuels like oil and nukes. But these numbers don't do anything but confuse and discredit.

    "When the going gets weird, the weird turn pro." - HST

    by DocGonzo on Thu Aug 19, 2010 at 09:38:47 PM PDT

    •  not for the real housewives of NJ mathematicians (0+ / 0-)

      19 million kilowatt hours a year total would deliver 58,010.0695 kilowatt hours each to only 327.529344 NJ homes. That's a lot different from 2,000.

      So far this year, the peak demand for electricity in the PJM region was 136,680 megawatts (MW) on July 6. Peak demand is the greatest amount of electricity used during a single hour. (One megawatt is enough electricity to serve 800 to 1,000 homes.) This peak amount was 14 percent higher than last year's peak demand. The all-time record peak demand was 144,644 MW set on August 2, 2006.

      "...calling for a 5" deck gun is not parody. Not by a long shot." (gnaborretni)

      by annieli on Thu Aug 19, 2010 at 10:01:47 PM PDT

      [ Parent ]

    •  According to New Jersey's Clean Energy ... (3+ / 0-)

      program, the average NJ residence uses 8400 kWh per year, not 58,000 kWh, 7x less. The average U.S. home consumes about 10,000 kWh annually.

      7 x 327 = 2289 homes.

      8440 x 2289 = 19,227, 600 kWh

      19,000,000 divided by 10,000 = 1900 homes.

      As for the wind turbines, they usually do generate - depending on wind speed, etc. - about one-third of rated capacity. In the earliest years (2005-2006), the Jersey-Atlantic site produced 21 million and 20 million kWh respectively.

      Don't tell me what you believe. Tell me what you do and I'll tell you what you believe.

      by Meteor Blades on Thu Aug 19, 2010 at 10:18:26 PM PDT

      [ Parent ]

      •  but you didn't carry it to the fourth decimal n/t (0+ / 0-)

        "...calling for a 5" deck gun is not parody. Not by a long shot." (gnaborretni)

        by annieli on Fri Aug 20, 2010 at 04:33:47 AM PDT

        [ Parent ]

      •  Energy vs Electricity (0+ / 0-)

        I believe the discrepancy is because the 58,000 KWh is the total energy the average NJ house uses, but 8400 KWh is the total electricity. I live in NY, effectively the same as NJ, and before I superinsulated my house it did use about 7x as much energy (actually somewhat more) for heating air & water as it did for electrical appliances & lighting.

        The windfarm article does say "energy for 2000 homes", but of course windmills produce only electricity. So it really should say "electricity for 2000 homes", since that's only a small fraction of the energy required for a NJ home, about 14%.

        "When the going gets weird, the weird turn pro." - HST

        by DocGonzo on Fri Aug 20, 2010 at 08:29:10 AM PDT

        [ Parent ]

Subscribe or Donate to support Daily Kos.

Click here for the mobile view of the site